Shaped objects for pyrogen retention and processes for their manufacture

Abstract

The invention describes hydrophilically acting shaped objects, in particular semipermeable membranes for pyrogen retention, comprising a synthetic polymer component and an additive made from a copolymer made from vinylpyrrolidone and a vinylimidazole compound, and furthermore processes for manufacturing the shaped objects. The shaped objects of the invention exhibit such a high pyrogen retention capacity that the pyrogen concentrations present in the filtrates are in part below the detection limit of the gel clot LAL test.</PTEXT>

What is claimed is:  
     
       1. A hydrophilically acting porous membrane for pyrogen retention, comprising: 
       a synthetic polymer component and an additive, wherein the additive is a copolymer made from vinylpyrrolidone and a vinylimidazole.  
     
     
       2. The hydrophilically acting shaped object according to  claim 1  having a porous structure. 
     
     
       3. The hydrophilically acting porous membrane according to  claim 1 , wherein the porous membrane is a flat, tubular or hollow-fiber membrane. 
     
     
       4. The hydrophilically acting porous membrane according to  claim 1 , wherein the copolymer is a statistic copolymer. 
     
     
       5. The hydrophilically acting porous membrane according to  claim 1 , wherein thc copolymer additive contains the vinylimidazole compound and vinylpyrrolidone in a molar ratio of from between 10 moles vinylimidazole compound to 90 moles vinylpyrrolidone and 90 moles vinylimidazole compound to 10 moles vinylpyrrolidone. 
     
     
       6. The hydrophilically acting porous membrane according to  claim 5 , wherein the molar ratio is about 50 moles vinylimidazole compound to about 50 moles vinylpyrrolidone. 
     
     
       7. The hydrophilically acting porous membrane according to  claim 1 , wherein the vinylimidazole compound is 1-vinylimidazole substituted at carbon atoms 2, 4, 5, and combinations thereof with a C 1 -C 5 -alkyl group. 
     
     
       8. The hydrophilically acting porous membrane according to  claim 1 , wherein the vinylimidazole compound is 1-vinylimidazole. 
     
     
       9. The hydrophilically acting porous membrane according to  claim 1 , wherein the additive is cross-linked. 
     
     
       10. The hydrophilically acting porous membrane according to  claim 1 , wherein the synthetic polymer component is a hydrophilic polymer. 
     
     
       11. The hydrophilically acting porous membrane according to  claim 10 , wherein the hydrophilic polymer is polyamide 6, polyamide 6,6, polyamide 4,6, polyethylvinyl alcohol or sulfonated polyethersulfone. 
     
     
       12. The hydrophilically acting porous membrane according to  claim 1 , wherein the synthetic polymer component is a mixture of a hydrophobic polymer and a hydrophilic modification of the hydrophobic polymer. 
     
     
       13. The hydrophilically acting porous membrane according to  claim 1 , wherein the synthetic polymer component comprises a hydrophobic first polymer arid a hydrophilic second polymer. 
     
     
       14. The hydrophilically acting porous membrane according to  claim 13 , wherein die hydrophobic first polymer is selected from the group consisting of polysulfones, polyethersulfones, polyarylethersulfones, polyacrylonitriles, polycarbonates, and polyolefins. 
     
     
       15. The hydrophilically acting porous membrane according to  claim 13 , wherein the hydrophilic second polymer is selected from the group consisting of polyvinylpyrrolidones, polyethylene glycols, polyvinyl alcohols, and sulfonated polyethersulfones.